This study represents a continuous effort to develop and establish the most reliable and reproducible method for culturing cerebromicrovascular endothelium derived from SJL mice susceptible to experimental allergic encephalomyelitis. The focus of the present investigation has been to analyze the nutritional requirements needed for sustained long-term growth and propagation of the endothelium. High concentration of endothelial cells grow equally well in medium containing 10-20% fetal calf serum (FCS). They required endothelial cell growth factor (ECGF) for maximal proliferation. Inclusion of heparin synergistically increased the proliferative response of the cells. In the presence of high concentration of FCS (20%), heparin surpassed ECGF in the ability to support increased proliferative response of the endothelium. A more detailed analysis of various nutrients is still required for establishment and characterization of long-term endothelial culture for expediting the investigation concerned with interaction between capillary endothelium and immune cells.